A user's typical response to a malfunctioning refrigerator is attempting to fix it on his own based on a measure provided from a service center or to ask the service center to dispatch a service person to handle the problem.
In such a way, however, the user cannot correctly let them know the erroneous symptoms of the refrigerator nor does the service center properly address the issue as well.
Recently, a way is being contemplated for the user to transfer the erroneous symptoms of the refrigerator to the service center, in which the symptoms of the refrigerator are converted into a signal sound that is then output and transferred to the service center through a phone. However, the signal sound transferred that way contains only information on the current state of the refrigerator but fails to convey information on the history of operations performed thus far. In particular, the refrigerator stays in operation all the time since power on, and in many case, cause of current errors is closely associated with the state in which the refrigerator has been recently operating. Thus, the conventional way of outputting only the information as to the current state as a signal sound cannot precisely diagnose the refrigerator.